Although the new insights into the universe of Harry Potter were welcomed by many, the author was strongly criticised online by a number of voices from Native American communities, particularly over her writing about skinwalkers, which in Navajo legend are said to be evil witches or wizards who can take on the form of animals.

Rowling writes that the myth “has its basis in fact … A legend grew up around the Native American Animagi, that they had sacrificed close family members to gain their powers of transformation. In fact, the majority of Animagi assumed animal forms to escape persecution or to hunt for the tribe. Such derogatory rumours often originated with No-Maj medicine men, who were sometimes faking magical powers themselves, and fearful of exposure.”

Responding to a question on Twitter, Rowling said that “in my wizarding world, there were no skinwalkers”, with the legend created by those without magic “to demonise wizards”.

But campaigner Dr Adrienne Keene told Rowling on Twitter that “it’s not ‘your’ world. It’s our (real) Native world. And skinwalker stories have context, roots, and reality … You can’t just claim and take a living tradition of a marginalised people. That’s straight up colonialism/appropriation.”

The academic also took issue with Rowling’s use of the phrase “the Native American community”, saying that “one of the largest fights in the world of representations is to recognise Native peoples and communities and cultures are diverse, complex, and vastly different from one another.”

This is clearly not legwork @jk_rowling did with this writing. Native communities use reciprocity, respect, and relationships as benchmarks.

“There is no such thing as one ‘Native American’ anything. Even in a fictional wizarding world,” wrote Keene on her blog, Native Appropriations. She continued: “Native spirituality and religions are not fantasy on the same level as wizards. These beliefs are alive, practised, and protected … we fight so hard every single day as Native peoples to be seen as contemporary, real, full, and complete human beings and to push away from the stereotypes that restrict us in stock categories of mystical-connected-to-nature-shamans or violent-savage-warriors”

Navajo writer Brian Young wrote on Twitter that he was “broken hearted” about the new piece of writing. “JK Rowling, my beliefs are not fantasy. If ever there was a need for diversity in YA lit it is bullsh!t like this,” said Young. “My ancestors didn’t survive colonisation so you could use our culture as a convenient prop.”

Johnnie Jae, founder of A Tribe Called Geek, described herself as a Potterhead who had “often thought of what it would be like if Natives were represented in this world”, but that the reality was “so disrespectfully done”.

Jae wrote: “This isn’t us saying that Native people can’t be wizards or magical beings, but that @jk_rowling’s attempt is unacceptable & disrespectful because @jk_rowling has based her ‘native wizards’ off the same racist stereotypes & miseducation that JM Barrie used in Peter Pan.”

We're saying that there is problem when non-natives continue to use outdated & racist stereotypes as the basis for their native characters

After she spoke out on Twitter, Keene said that she had been deluged with responses, “with the typical accusations of my oversensitivity and asking if I understand that Harry Potter is fictional, and more directed hate telling me my doctorate is being misused and I’m an idiot.

“Also worthy of note is that Rowling is known for responding directly to fan questions on Twitter, and overall being accessible to her fanbase. Despite thousands of tweets directed at her about these concerns, she has not addressed it at all. The silence is noted, and it’s deafening,” wrote Keene.

Rowling’s representatives have yet to respond to a request for comment.